Post-conventional is the highest level of moral reasoning based on cognitive developmental moral theory. As the highest level, post-conventional is the level of moral reasoning that everyone (including Muslims) needs to have because a person's moral reasoning is correlated with his moral actions. Moral reasoning affects how a person believes that behavior should be done. A person has reached the post-conventional level if his moral reasoning refers to universal values such as justice, equality, humanity, and so on. In Muslim society, the acceptance of universal values that form the basis for this post-conventional level of moral reasoning is still debated. This article examines the thoughts of Muslim scholars who present explanations of Islamic scientific tools (maqashid al-shariah, maslahah, and naskh-mansukh), which give place to universal principles. The results of this study conclude that a Muslim has the opportunity to reach a post-conventional moral level because his religious teachings provide a foundation based on universal values as well as a post-conventional moral level foundation. Based on the results of this study, Islamic education can use the reference of cognitive-developmental moral theory to be used in the formation of students' moral reasoning to the highest level; post-conventional.